The exact circumference of a circle is 18T
inches. What is the approximate area of the
circle? Use 3.14 for π. Round to the nearest
hundredth if necessary. (Example 4)



Answer :

To find the area of a circle, we use the formula: \( A = \pi r^2 \), where \( \pi \) is approximately 3.14 and \( r \) is the radius of the circle.

Given that the circumference of the circle is \( 18\pi \) inches, we can find the radius using the formula for circumference: \( C = 2\pi r \).

So, \( 18\pi = 2\pi r \).

Dividing both sides by \( 2\pi \), we get:

\( r = \frac{18\pi}{2\pi} = 9 \) inches.

Now, we can plug the radius into the formula for the area of a circle:

\( A = \pi \times (9)^2 = 81\pi \) square inches.

Since \( \pi \) is approximately 3.14, we can approximate the area:

\( A \approx 81 \times 3.14 = 254.34 \) square inches.

Rounded to the nearest hundredth, the approximate area of the circle is 254.34 square inches.